WEBVTT

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Find the area and the perimeter of the polygon

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so lets start with the area first

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so the area of this polygon

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and there's kind of two parts to this

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first you have this part that's kind of rectangular

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or it is rectangular

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this part right over here

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and that area is pretty straightforward

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it's just going to be base times height

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so the area's going to be 8 times 4

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8 times 4 for the rectangular part

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and then we have this triangular part up here

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so we have this area up here

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and for a triangle this area is base times height times 1/2

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that actually makes a lot of sense

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because you just multiply base times height

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you would get this entire area

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you get the area of the entire rectangle

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and you see that the triangle is exactly half of it

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if you took this part of the triangle

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and you flip it over, you'd fill up that space

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and you took this part of the triangle

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and you flip it over, you'd fill up that space

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so the triangle's area is half of

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the triangle's base times the triangle's height

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so plus 1/2 times the triangles base which is 8 inches

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and the triangles height which is 4 inches.

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so let us calculate it this gives us

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it is not 4, triangles height is 3, so let us go back

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and calculate it area = 32 + 1/2 * 8*3 = 32 + 12 = 44

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area of the figure is 44

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now let us do the perimeter.We need to figure out the

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sum of the sides. If we need to put a fence

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what is the length that we need to cover

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so the perimeter = 8+4+5+5+4 =26 inches

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Let me get the unit right, here we are multiplying

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8 inches by 4 inches we get 32 square inches and

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here we multiply 8 inches by 3 inches we get 24 square inches

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divide by 2 we get 12 square inches.

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area = 44 square inches, perimeter is 26 inches

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area is two dimensional and perimeter is one dimensional